Fix #40 Fully qualify type in a switch statement

src/Zomp.SyncMethodGenerator/AsyncToSyncRewriter.cs

@@ -944,6 +944,12 @@ bool ShouldRemoveAttribute(AttributeSyntax attributeSyntax)
         return @base.WithType(ProcessType(node.Type)).WithTriviaFrom(@base);
     }
 
+    public override SyntaxNode? VisitDeclarationPattern(DeclarationPatternSyntax node)
+    {
+        var @base = (DeclarationPatternSyntax)base.VisitDeclarationPattern(node)!;
+        return @base.WithType(ProcessType(node.Type)).WithTriviaFrom(@base);
+    }
+
     public override SyntaxNode? VisitTypeOfExpression(TypeOfExpressionSyntax node)
     {
         var @base = (TypeOfExpressionSyntax)base.VisitTypeOfExpression(node)!;

tests/Generator.Tests/Snapshots/TypeTests.SwitchType#SwitchAsync.g.verified.cs

@@ -0,0 +1,9 @@
+//HintName: Test.Class.SwitchAsync.g.cs
+public void Switch(global::System.IO.Stream stream)
+{
+    var s = stream switch
+    {
+        global::System.IO.FileStream fs => fs,
+        _ => throw new global::System.InvalidOperationException("No"),
+    };
+}

tests/Generator.Tests/TypeTests.cs

@@ -76,4 +76,17 @@ public Task HandleTypeOf()
     public Task HandleNameOf()
         => "_ = nameof(Stream);"
         .Verify(sourceType: SourceType.MethodBody);
+
+    [Fact]
+    public Task SwitchType() => """
+[CreateSyncVersion]
+public async Task SwitchAsync(Stream stream)
+{
+    var s = stream switch
+    {
+        FileStream fs => fs,
+        _ => throw new InvalidOperationException("No"),
+    };
+}
+""".Verify();
 }